1. Field of the Invention
The present invention relates generally to the shaker tables to which manufactured devices are mounted for vibrational testing. More particularly, the present invention relates to a specific mounting table, the exciters or vibrators mounted thereto, and the means to inhibit thermal transfer from the device and mounting table to the exciters or vibrators.
2. Description of the Prior Art
Shaker tables for testing the reliability of manufactured devices are well known. Such shaker tables are used either under laboratory conditions or in conjunction with an assembly line. Often, shaker tables are mounted within thermal chambers, which gives the added flexibility of testing for defects in the manufactured product which may be exposed by elevated temperature or temperature cycling.
The shaker tables typically include a platform or mounting table upon which a device to be tested is mounted. Exciters or vibrators are attached to the mounting table to vibrate the device. It is necessary to provide an even distribution of the vibration amplitude, magnitude, direction and frequency in a range. Typical of such arrangements is U.S. Pat. No.4,735,089 issued to Richard L. Baker, et al. That patent and others attempt to establish a uniform amplitude to the mounting table from the exciters over the range of frequencies generated.
The Baker patent identifies a problem with rigid shaker tables in achieving the objective of creating random vibration of substantially equal amplitude over the range of frequencies in a multi-axial direction. Baker does so by use of a flexible shaker table that is said to resolve potential resonance problems normally inherent in rigid mounting tables. The end result of this multi-axial excitation is a relatively complex mounting table or platform, having multiple layers, multiple connectors and multiple potential wear points.